Viruses

What is a Virus?

A virus is only a program, like any other on your computer. What makes a virus "special" is the fact that it replicates, or makes copies of itself. These copies, whether intended to be harmful or not can cause serious problems to information stored on your computer.

Types of viruses:

• System Sector Viruses (also known as boot sector viruses) reside in your system software, and are executed every time you boot up you disk. These viruses can also infect the boot sector of diskettes.

• File Viruses infect programs, and spread every time the host program is exited.

• Trojan Horse Programs are considered another type of virus, according to some, but not all, experts. Trojans, as their name implies, have a useful facade, but have an ulterior mission which occurs when the user executes the program.

Viruses can NOT:

• Be spread by being connected to an on-line service.
• Be spread by opening e-mail.
• Affect your hardware.

Viruses:

• Must be executed to be spread.
• Are most commonly spread by infected diskettes.

Once you understand a bit about viruses, they can best be avoided by use of an anti-viral software and, most of all, by avoiding the use of suspect diskettes. Be aware that anti-viral software can only detect known viruses, and therefore it is not foolproof. In addition it must be updated regularly as the number of "known" viruses increases.

The following are freeware and shareware programs for use on the major operating systems.

For Windows95 VirusSCAN1.15

For Macintosh Disinfectant 3.6

For OS/2 CPAV

Some excellent sources for additional information are:

• Stiller Research Home Page
• Symantec Anti-Virus Reference Center
• McAfee Home Page
• Technology and Security
• Manitoba Virus Information

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Please send comments about this page to Gary Roth at garth@interport.net .